It is known to seed water contaminated with suspended matter, with magnetic material and to use an electromagnetic field to remove the magnetic material and suspended matter. Illustrative of this type of prior art is U.S. Pat. No. 2,232,295 to Urbain, et al., U.S. Pat. No. 2,398,725 to Schutte, U.S. Pat. No. 3,697,420 to Blaisdell, et al., U.S. Pat. No. 3,923,651 to Weiss, et al., U.S. Pat. No. 3,983,033 to de Latour, U.S. Pat. No. 4,089,779 to Neal, U.S. Pat. No. 4,110,208 to Neal, U.S. Pat. No. 4,115,262 to Gustavsson, et al., and U.S. Pat. No. 4,141,687 to Forrest, et al. In certain of this prior art, the use of a positively-charged electrolyte in combination with the magnetic material is known. Exemplary of this art are the Urbain, et al., Blaisdell, et al., and de Latour patents. Certain of these three patents also show the use of flocculating agents that are negatively charged.
Magnetic fluids are also well known in the prior art. Illustrative magnetic fluids are found in U.S. Pat. No. 3,764,540 to Khalafalla, et al., and U.S. Pat. No. 3,843,540 to Reimers, et al. The magnetic fluid of the latter patent is colloidal and has an organic base, such as kerosene. Moreover, use of an organic-base, magnetic colloid of this type for separating non-magnetic particles of different densities is known. U.S. Pat. No. 4,085,037 to Quets, et al. is exemplary.
However, this prior art and the other prior art of which we are aware is deficient in that it is believed that the methods thereof do not provide for particle-to-particle titration, which results in the need for a very small volume of our magnetic colloid to clarify slimes; do not provide for the combination of particle-to-particle titration and a settling time that requires only minutes; and do not, in turn, permit the use of a settling tank that is significantly smaller than that conventionally used, due to the required brief residence time.